Solid State Circuits 9 - H-Mode Mixer

Version 5.6 (hopefully the final version!) Is shown in the above circuit. The construction has been simplified and the layout amended from previous versions to correct some minor errors in component spacings. The squarer now uses three separate ultra high speed 5 volt inverters type NC7SZ04 to improve the VHF response and reduce the current consumption above 50MHz. The version 5 PCB layout document is available here - the PCB is made from doubled sided FR4 or G10 fibreglass. This is my preferred version for home prototype construction with as few SMT components as possible to make the assembly easier. A number of the decoupling capacitors have one leg soldered to the top copper The symbol explanation document is here.

A surface mount component PC board of a similar size is currently in development and will be shown here as soon as manufacture and tests are complete.

Warning: The seven surface mount ICs used in this version are more fragile and susceptible to damage from excess voltages, electrostatic charges etc compared to previous versions. It is recommended that each module be completely isolated from all equipment before any work including soldering is carried out. I have inadvertently damaged several ICs by not following these rules.

This page shows my latest version of the H-Mode mixer originally developed by Colin Horabin G3SBI and subsequently revised by Giancarlo Moda I7SWX and Martein Bakker PA3AKE.

The original mixer design may be found at: CDG2000 Transceiver.htm

IK4AUY has also done significant work on the H-Mode mixer - see here.

The latest work by PA3AKE can be seen here.